Facile and Selective Synthetic Approach for Ruthenium Complexes Utilizing a Molecular Sieve Effect in the Supporting Ligand

Abstract

It is extremely important for synthetic chemists to control the structure of new compounds. We have constructed ruthenium-based mononuclear complexes with the tridentate 2,6-di(1,8-naphthyridin-2-yl)pyridine (dnp) ligand to investigate a new synthetic approach using a specific coordination space. The synthesis of a family of new ruthenium complexes containing both the dnp and triphenylphosphine (PPh3) ligands, [Ru(dnp)(PPh3)(X)(L)]n+ (X = PPh3, NO2−, Cl−, Br−; L = OH2, CH3CN, C6H5CN, SCN−), has been described. All complexes have been spectroscopically characterized in solution, and the nitrile complexes have also been characterized in the solid state through single-crystal X-ray diffraction analysis. Dnp in the present complex system behaves like a “molecular sieve” in ligand replacement reactions. Both experimental data and density functional theory (DFT) calculations suggest that dnp plays a crucial role in the selectivity observed in this study. The results provide useful information toward elucidating this facile and selective synthetic approach to new transition metal complexes.

Keywords

• synthesis
• ruthenium complex
• polypyridyl ligand
• crystal structure
• DFT calculation